Comparative analyses of eighteen rapid antigen tests and RT-PCR for COVID-19 quarantine and surveillance-based isolation

• Published in: Communications medicine Vol. 2; no. 1; pp. 84 - 12
• Main Authors: Wells, Chad R., Pandey, Abhishek, Moghadas, Seyed M., Singer, Burton H., Krieger, Gary, Heron, Richard J. L., Turner, David E., Abshire, Justin P., Phillips, Kimberly M., Michael Donoghue, A., Galvani, Alison P., Townsend, Jeffrey P.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 09-07-2022; Nature Portfolio
• Subjects: 692/699/255; 692/700/478/174; 692/700/478/2772; Medicine; Medicine & Public Health; Epidemiology; Population screening; Infectious diseases
• ISSN: 2730-664X; 2730-664X
• DOI: 10.1038/s43856-022-00147-y

Background
Rapid antigen (RA) tests are being increasingly employed to detect SARS-CoV-2 infections in quarantine and surveillance. Prior research has focused on RT-PCR testing, a single RA test, or generic diagnostic characteristics of RA tests in assessing testing strategies.
Methods
We have conducted a comparative analysis of the post-quarantine transmission, the effective reproduction number during serial testing, and the false-positive rates for 18 RA tests with emergency use authorization from The United States Food and Drug Administration and an RT-PCR test. To quantify the extent of transmission, we developed an analytical mathematical framework informed by COVID-19 infectiousness, test specificity, and temporal diagnostic sensitivity data.
Results
We demonstrate that the relative effectiveness of RA tests and RT-PCR testing in reducing post-quarantine transmission depends on the quarantine duration and the turnaround time of testing results. For quarantines of two days or shorter, conducting a RA test on exit from quarantine reduces onward transmission more than a single RT-PCR test (with a 24-h delay) conducted upon exit. Applied to a complementary approach of performing serial testing at a specified frequency paired with isolation of positives, we have shown that RA tests outperform RT-PCR with a 24-h delay. The results from our modeling framework are consistent with quarantine and serial testing data collected from a remote industry setting.
Conclusions
These RA test-specific results are an important component of the tool set for policy decision-making, and demonstrate that judicious selection of an appropriate RA test can supply a viable alternative to RT-PCR in efforts to control the spread of disease.
Plain language summary
Previous research on SARS-CoV-2 infection has determined optimal timing for testing in quarantine and the utility of different frequencies of testing for infection surveillance using RT-PCR and generalized rapid antigen tests. However, these strategies can depend on the specific rapid antigen test used. By examining 18 rapid antigen tests, we demonstrate that a single rapid antigen test performs better than RT-PCR when quarantines are two days or less in duration. In the context of infection surveillance, the ability of a rapid antigen test to provide results quickly counteracts its lower sensitivity with potentially more false positives. Our findings indicate that rapid antigen tests can be a suitable alternative to RT-PCR for application in quarantine and infection surveillance.
Wells et al. use mathematical modeling to compare quarantine duration, testing frequency, and false-positive rate for 18 rapid antigen (RA) and RT-PCR tests. They show that the relative effectiveness of RA and RT-PCR tests in reducing post-quarantine transmission depends on the quarantine duration, the timing of their use in the infection time course, and the turnaround time of test results.